Shaft-packing



. J. WILKINSON.

SH AAAAAAAAAA G. APPLICATION FILED MAY 9. m

9' 1,394,959, Patented Oct. 25, 1921a m 2 SHEETSSHEET l.

Inventor":

JamesWilKinson,

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SHAFT P AAA A Patented Oct. 25, 1921..

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a UNITED sTATEs PATENT. OFFICE.

JAMES WILKINSON, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

' SHAFT-PACKING.

Specification of Letters Patent.

Application filed May 9, 1919. Serial No. 295,980.

such as are used to prevent leakage of fluid between two relatively rotating'parts. Such packings are used, for example, in connection with rotating shafts to prevent leakage between a shaft'andan adjacent wall through which it passes, one well-known application being found in connection with elastic fluid turbines.

The invention relates more particularly to packings of the liquid seal type and has for its object to provide an improved structure in packings of this character.

For a consideration of what I believe to to be novel and my invention attention is directed to the accompanying description and the claims appended thereto.

In the drawing, Figure 1 is a longitudinal radial sectional view of a packing embodying my invention; Fig. 2 is a section taken on line 22, Fig. 1, and Figs. 3 and 4 are views, similar to those of Figs. 1 and 2 respectively, showing another embodiment of my invention.

Referring to the drawing, (Figs. 1 and 2) 5 indicates a rotating shaft and 6 a casing having an opening 7 through which the shaft passes and between which and the shaft it is desired to'prevent leakage. Bolted to the casing 6 at opening 7 is a housingoomprising an inner end wall 8, an outer end wall 9. and an annular side wall 10, preferably formed integral with walls 8 and 9. In the present instance one-half of wall 10 is formed integral with end wall 8 and the other half is formed integral with wall 9. Walls Sand 9 are fastened to casing 6 by means of a flanged ring 11 fastened to casing 6 by bolts 11". Carried by shaft 5 inside the housing is an impeller 12 having on its opposite sides suitable vanes 13 which are closed by side plates let. Side plates 1% are fastened to the vanes by means of rivets'15. Impeller 12 has a peripheral rim 16 of the same width as vanes 13 and between rim 16 and the inner wall of the housing is a slight clearance forming annular passages 17 and 18. In annular wall 10 surrounding impeller 12 is a continuous groove 19, and communigroove 19 so there is a complete ring of liquid around the periphery of the impeller. The outer periphery of side plates 11. are cut away to form annular chambers 22 to which impeller 12 when operating delivers liquid, and chambers 22 are in communication with groove 19 through passages 17 and 18 and they are in communication with the spaces between side plates 14 and end walls 8 and 9 through annular clearance spaces 23 and 2-1. There is considerable clearance between side plates 11 and end walls 8 and 9 and at their radially inner portions such side plates and end walls are provided with interleaving annular rings 25 and 26 respectively, thus forming a labyrinth packing. Impeller 12 is provided with hub extensions 27 on which are cut threads 28 which run in directions to pump any liquid which falls on the shaft back to the impeller. thread will be left hand and the other right hand. i

In operation, sealing liquid, such as water,

is supplied through pipe 21 to annular groove 19 and from here liquid will {be fed to the impeller which acts by centrifugal force to establish a liquid seal to prevent leakage. Assuming for example. that the pressure on the left hand side of the packing is greater than that on the right hand side, then a liquid seal will be estalr lished having a stati head of a height in dicated 'at (2 depending among other things on the difference in pressure on the two sides of the packing.

The impeller vanes 13 act as a pump taking water at their radially inner or suction ends and delivering it at their radially outer or discharge ends. The water received at the inner ends of the vanes is that which is discharged from the outer ends and flows to the inner ends through the path between side plates 11 walls 8 and 9. This flow, which is in the nature of local circulation, will be. greater on the low pressure side of the packing than it is on the high pressure side of the packing.

After the liquid seal is established, how

For this purpose one 

